PB2002: OBSERVATIONAL PROSPECTIVE STUDY TO INVESTIGATE THE RELATIONSHIP BETWEEN DURATION OF TREATMENT AND RESPONSE IN PATIENTS WITH MULTIPLE MYELOMA OR AL AMYLOIDOSIS: THE DORIANT STUDY (NCT: 04659798)
Authors: M. Grande, A. Naves, J. Aparicio, M. Gironella
Journal: HemaSphere (2022)

Background: The introduction of new drugs with a lower toxicity profile and the increasing evidence regarding the benefits of continuous over fixed-duration therapy have progressively shifted the therapeutic approach for patients with multiple myeloma (MM) from the traditional fixed duration strategy to continuous regimens. Patients with MM often discontinue treatment in clinical practice before the foreseen time. Treatment duration may depend on multiple factors, including patient’s baseline characteristics, available drugs, treatment response, progression, or toxicity. Despite the rising evidence regarding the influence of treatment duration on therapeutic outcomes, the determinants of treatment duration and its relationship with survival in real-life practice have been little investigated, including reasons for treatment discontinuation. Moreover, this research on the influence of treatment duration and outcomes such as survival has mainly focused on MM, while it has hardly been investigated in monoclonal gammopathies treated with similar therapeutic approaches, such as systemic AL amyloidosis. Aims: To investigate the relationship between duration of treatment according to selected treatment strategy (fixed vs. continuous) and response to treatment among patients diagnosed with MM and/or AL amyloidosis. We provide an update regarding the characteristics of the population currently enrolled. Methods: Prospective, non-interventional, multi-center study in real-life practice in 14 Spanish hospitals. The study included subjects aged 18 or older diagnosed with MM and/or AL amyloidosis who started treatment up to 12 months before the inclusion. The study is planning to enroll 250 patients (220 with MM and 30 with AL amyloidosis). Results: Of the 181 patients enrolled, 164 (90.6%) were included in the analysis; 145 (88.4%) of them were diagnosed with MM, 11 (6.7%) with AL amyloidosis, and 8 (4.9%) with both diseases. The median age was 74.0 (68.0-79.0) years for MM patients, 76.0 (70.0- 83.0) years for AL amyloidosis patients, and 67.5 (56.5- 70.5) years for patients with both diseases. Among patients diagnosed with MM therapy strategy data (n=116), 32 (27.6%) received fixed-duration therapy, and 84 (72.4%), continuous therapy. Among patients diagnosed with AL with therapy strategy data (n=11), 1 (9.1%) received fixed-duration therapy and 10 (90.9%) continuous therapy. Of the 7 patients with both diseases and therapeutic strategy, 4 (57.1%) received fixed-duration therapy, and 3 (42.9%), continuous therapy. Of the patients diagnosed with MM (n=116), 62 (53.4%) were on first line (1L), 30 (25.9%) on second line (2L), 16 (13.8%) on third line (3L), and 8 (6.9%) on fourth line (4L). Among 11 patients diagnosed with AL amyloidosis, 6 (54.5%) were on 1L and 5 (45.5%) on 2L, and over 8 patients with both diseases, 3 (37.5%) were on 1L, 3 (37.5%) on 2L, 1 (12.5%) on 3L, and 1 (12.5%) on 4L. Over 94 MM patients with treatment type data, 14 (14,9%) received consolidation and/or maintenance treatment. Of these patients (n=14), 1 (7.1%) received consolidation; 9 (64.3%), maintenance, and 4 (28.6%), consolidation and maintenance. No patients with AL amyloidosis received consolidation or maintenance treatment. Summary/Conclusion: In the patients analyzed to date, continuous treatment was the most common therapeutic strategy, regardless of the disease. This study will provide insights into determinants of treatment duration and its relationship with survival in real-life practice, which might help clinicians manage MM and AL amyloidosis.